Don't count on getting bumped.

I've been on the phone with a corporate travel agent and asked for a "waitlist" booking for a "sold out" flight. Before the call ended the booking cleared, and I bought the ticket. I think this is fairly common, that JAL will hold back a few seats for their preferred travel agents. Sold out flights really aren't, from what I can tell.

I've had other waitlist bookings. Only one didn't clear, but I didn't give it much time since I had to change flights anyway. A couple days ago I arrived at the airport to stand by for an earlier "sold out" flight. I ended up with a perfectly fine aisle seat and a boarding pass right away.